The importance of summer cattle mineral supplementation

Most cattle producers provide minerals and vitamin supplements during winter and spring, but some may not provide those supplements when pastures are green and growing. This practice might cut production costs in the short term, but it can prove extremely costly in the long run.

Minerals and vitamins are a very small but extremely important element of cattle nutrition, playing vital roles in reproduction, immunity and growth. Cattle who do not receive proper mineral and vitamin nutrition will not grow or reproduce as quickly or efficiently as their well-supplemented counterparts.

Minerals are loosely grouped into two categories: macro-minerals and trace or micro-minerals. Macro-minerals — including calcium, phosphorus, magnesium, potassium, sulfur and salt — are needed in relatively large amounts in the body. Micro-minerals — such as cobalt, copper, iodine, iron, manganese, selenium and zinc — are needed in very small, or “trace,” amounts. Vitamins A, D and E are among those that are typically supplemented. Details about the key nutrients that are more likely to be deficient in summer forages are included below.


Phosphorus is vitally important for growth, milk production and fertility. Cattle on summer pasture are often at least marginally deficient in phosphorus. Cow requirements for spring-calving herds are much higher early in the grazing period through breeding, so supplemental phosphorus is critical during this period. Phosphorus supplementation should also continue after breeding, since forage phosphorus levels decrease steadily as forages mature. Common deficiency symptoms include breeding problems, such as reduced conception rates, and reduced average daily gains.


Copper is critical for both fertility and immunity. Many U.S. soil types are marginally to severely deficient in copper, meaning most U.S. cattle require copper supplementation. Inadequate copper levels will result in decreased conception rates, early embryo deaths, decreased ability to respond to immune challenges and faded hair coats.


Selenium is also important for reproduction and immunity. Selenium supplementation can help prevent retained placentas, uterine infections and white muscle disease. Most of the soils in the U.S. are marginal to deficient in selenium, so selenium supplementation is often necessary.


Zinc plays a role in the maintenance of skin, hooves, gut linings and the lining of the reproductive organs. Deficiencies will result in decreased fertility, skin problems, hoof and joint problems, and decreased average daily gains due to decreased nutrient absorption. Providing these minerals to bulls throughout the year is important — especially during the summer breeding season.

Vitamin A

Vitamin A is typically abundant in green growing forages but is less plentiful in mature or drought-stricken forages. Cattle under stress (during weaning, lactation, transportation, etc.) have higher vitamin A requirements than normal and benefit from supplementation. Inadequate levels of vitamin A result in stunted growth, reproductive disorders, runny eyes and an increased susceptibility to diseases like pinkeye.

While most cattle can survive on the levels of minerals and vitamins in the available forages, the vast majority of cattle are not receiving what is necessary for producing at high levels and improving efficiency. It is important to remember that the mineral content of forages is generally limited by the mineral make-up of the soils in which they grow; if it’s not in the soil, it can’t get into the plant. And, while soil types vary, no one soil type provides optimal levels of all the minerals cattle need. In fact, some soils are severely deficient in some minerals (e.g., selenium or copper) or have an overabundance of one mineral that interferes with the availability of another mineral (e.g., high sulfur levels interfere with copper and selenium uptake and utilization). For this reason, making free-choice mineral and vitamin supplementation available to cattle at all times is often recommended.

If you feed salt or trace mineralized salt as a supplement during the summer, you may think that you are giving cattle what they need — but, while cattle do need salt, their nutritional needs are not necessarily met by salt blocks or trace mineralized salt blocks alone. Trace mineralized salt blocks are mostly salt (typically 92 to 98 percent) and contain relatively low levels of trace minerals. Because of their high salt content, consumption of these blocks will be very low, resulting in poor intake levels of the needed trace minerals. Additionally, these blocks do not contain the macro-minerals or vitamins cattle need. A complete mineral/vitamin supplement will provide both the necessary macro- and micro-minerals as well as the vitamins.

Mineral and vitamin supplementation should be thought of as an insurance policy. Maintaining high-quality pastures for your cattle will help you meet the majority of their nutritional needs, but also providing free-choice access to a complete mineral and vitamin supplement will help ensure that ALL of your cattle’s nutritional needs are being met.

SWEETLIX® offers a wide range of high-quality mineral and vitamin supplements to ensure that your cattle’s nutritional needs are met, not only in the summer, but year-round. Additionally, these minerals come in a variety of forms; convenient pressed blocks, poured blocks, low-moisture blocks or loose minerals are all available from SWEETLIX to best fit your management style and your cattle’s needs.  Also, check out our new Blueprint® line of minerals, provided in a highly bioavailable form to meet the advanced demands of today’s modern genetics and to protect the environment from unnecessary over-supplementation through less bioavailable mineral forms.

Ask for SWEETLIX by name at your local SWEETLIX dealer or call 1-87-SWEETLIX for more information.